1. Field of the Invention
The present invention is in the field of medical apparatus and more specifically relates to an improvement in a hypodermic syringe to render the syringe more tamper-resistant.
2. The Prior Art
A fractional cross-sectional view through a portion of a syringe of the prior art is shown in FIG. 1. FIG. 1 shows the end of the hypodermic syringe that is opposite the end to which the needle is attached. As shown in FIG. 1, the hypodermic syringe includes a tubular member 12 of glass or other transparent material which serves to contain the fluid 14. A drive piston 16 of a soft rubber is included within the tubular member 12 and forms a slidable seal with the inside surface of the tubular member 12. A screw 18 is embedded in the drive piston 16 to permit an actuating rod (not shown) to be connected to the drive piston 16. The actuating rod facilitates application of a force, directed leftward in FIG. 1, to the drive piston 16 leftward for the purpose of expressing the fluid 14 from the syringe.
Instances have been discovered in which a person has inserted a needle 20 in the manner shown in FIG. 1 through the drive piston 16 to aspirate some of the fluid (narcotics). An object of the present invention is to prevent this type of pilfering.